The word ‘migration’ usually refers to the movement of human, specially a whole group, from one place to another. The history of migration began as soon as human was created. The reason was easy- collecting food from the nature .Moreover, finding a safe place to protect themselves from natural disasters and wild animals encouraged to migrate. In migration and out migration are used for, internal migration meaning inside the national territory while crossing the boundary is identified as international migration.
Animal also migrate from one place to another, like the humans, and this migration is more rapid than the humans. Some animals like wild beast and sooty Shearwater traveled the world from their birth to death, thousands of miles every year. This traveling may cross the boundary or not , they dare about this , but is the only way to keep themselves alive in the world. Human migrates once, twice or more, but animals , like Pacific salmons, pass their life with migration . Some specifies of pacific salmon born in freshwater streams , travel to ocean waters and then return to breed before dying.
Almost all animal migrate from one place to another for searching foods but some of them traveled long distances. Wildebeests, elephants, Reindeer , Zebra and Caribou are some animals that traveled regularly.
Fishes like various species of shark and whale, dolphins , hundreds of miles every year. Birds , mostly known as migratory birds , are large among the migrates. About thousand types of birds travel the world every year . Various types of goose like great crested grebe, widgeon, egret , large egret, heron, night heron, snipe etc. as well as fruit bat , nightingale, humming bird, cockatoo are mentionable.
REASONS OF MIGRATION
Animal also migrate from one place to another, like the humans, and this migration is more rapid than the humans. Some animals like wild beast and sooty Shearwater traveled the world from their birth to death, thousands of miles every year. This traveling may cross the boundary or not , they dare about this , but is the only way to keep themselves alive in the world. Human migrates once, twice or more, but animals , like Pacific salmons, pass their life with migration . Some specifies of pacific salmon born in freshwater streams , travel to ocean waters and then return to breed before dying.
Almost all animal migrate from one place to another for searching foods but some of them traveled long distances. Wildebeests, elephants, Reindeer , Zebra and Caribou are some animals that traveled regularly.
Fishes like various species of shark and whale, dolphins , hundreds of miles every year. Birds , mostly known as migratory birds , are large among the migrates. About thousand types of birds travel the world every year . Various types of goose like great crested grebe, widgeon, egret , large egret, heron, night heron, snipe etc. as well as fruit bat , nightingale, humming bird, cockatoo are mentionable.
REASONS OF MIGRATION
Some reasons lied behind the migration. Animals that live in habitats that are difficult to survive in year round, must evolve a way to cope with the difficult time of year. A common strategy is hibernation, used by many mammals and other species. Snakes, white bear, and some animals in the winter season follow this technique. Others follow the rest option, migration, and move across long distances. They survive by leaving the area for part of the year, sometimes even part of their live, and move to habitats that are more hospitable. Taking the advantages of food , shelter and water that vary with seasons , or life stage is the most common reason to migrate. The availability of food and water can change throughout the year. For instance, when winter suddenly halts the supply of insects, birds that insects must head for warmer climates where food is still bountiful. Similarly when the cold settles in, small rodent and birds that are prey for predatory birds become scarce, so the north American red tailed hawk flies Mexico or the Gulf coast to find a more abundant food source. Sometimes , deep snow may make animals easier to catch by predators , or make the water ice. So finding a new place full of food is emergency case.
Plant eating mammals like buffalo and antelope; typically graze in herds, which can deplete the grass in an area. These animals instead of waiting for grass, go a short distance to find new grass, circling back to the original area when grass is abundant again. But in winter, grass does not regrow, so the herds move back to the areas where they found good the previous season. During the climatic changes like drought , water holes draw both the predators and prey, making these areas both overcrowded and dangerous in Africa, wildebeests, zebra and other prey species therefore migrate to areas where water is more plentiful. Bear the young in places relatively safe from predators and rich in resources, a more important reason of migration, also encourage the animals. For instance some right whales leave their Antarctic feeding grounds where their primary food resource is plentiful. They travel to bear their young.
Green turtle, another reproductive migrant, swim from their feeding grounds off the coast of Brazil during the time of lying eggs. After long swim, about 2000 km, they haul themselves onto sandy beaches, scrape out shallow nests, and deposit their eggs. Like the green turtles, freshwater eels trace ancient migratory patterns, swimming from each side of the Atlantic to the weedy Sargasso Sea and return after breeding.
Navigation of migration
Plant eating mammals like buffalo and antelope; typically graze in herds, which can deplete the grass in an area. These animals instead of waiting for grass, go a short distance to find new grass, circling back to the original area when grass is abundant again. But in winter, grass does not regrow, so the herds move back to the areas where they found good the previous season. During the climatic changes like drought , water holes draw both the predators and prey, making these areas both overcrowded and dangerous in Africa, wildebeests, zebra and other prey species therefore migrate to areas where water is more plentiful. Bear the young in places relatively safe from predators and rich in resources, a more important reason of migration, also encourage the animals. For instance some right whales leave their Antarctic feeding grounds where their primary food resource is plentiful. They travel to bear their young.
Green turtle, another reproductive migrant, swim from their feeding grounds off the coast of Brazil during the time of lying eggs. After long swim, about 2000 km, they haul themselves onto sandy beaches, scrape out shallow nests, and deposit their eggs. Like the green turtles, freshwater eels trace ancient migratory patterns, swimming from each side of the Atlantic to the weedy Sargasso Sea and return after breeding.
Navigation of migration
It is quiet a surprising matter about finding the same route while migration. The mystery of animal migration remains one of the most compelling in science. Much work has been done on orientation and navigation in migrating animals, although the subject is still not well understood. Studies of salmon indicate that they depend on the olfactory sense to locate and return to their stream of origin. Herbivorous mammals often follow well established trails and probably also use their sense of smell. Bats, whales and seals use echolocation to navigate in the dark or underwater .
In shorter migration, animals do not need complicated navigation abilities. They can simply follow the food or the water, or head downhill to the valleys in winter and back up toward the ridges in summer. In longer migration, according to the scientists, animals use senses and sun, stars and geographic features. For instance, Starlings orient themselves using the sun, compensating for how the sun moves across the sky throughout the day. Mallard ducks can find north using the stars of the night sky. On the other hand, loggerhead turtles have the ability to sense the direction and strength of Earth magnetic field, which they use for navigating along the turtles ‘regular migration route. Animals can also use mental maps like human beings. They just become familiar with an area and navigate using mountain ranges, coastlines, rivers and even, like dolphins, the shape of the sea floor. Smell is also a powerful tool for navigation. Salmon uses smell to find the exact stream that they were born.
Migratory birds are believed to use the stars, sun and other geographic features as guides. Night migrating birds are sometimes disoriented in prolonged heavy fog. Day- flying birds navigate by the sun and also make some use of geographic features , particularly of shorelines, most migratory birds travel within broad north-south air routes known as flyways. Some migratory bird’s winter only a few hundred miles from their breeding grounds, while other migrate between the cold or temperate zones of the two hemispheres. The longest journey is made by the Arctic tern, a small bird that flies from the Arctic to the Antarctic and back again each year.
Hazards of migration:
In shorter migration, animals do not need complicated navigation abilities. They can simply follow the food or the water, or head downhill to the valleys in winter and back up toward the ridges in summer. In longer migration, according to the scientists, animals use senses and sun, stars and geographic features. For instance, Starlings orient themselves using the sun, compensating for how the sun moves across the sky throughout the day. Mallard ducks can find north using the stars of the night sky. On the other hand, loggerhead turtles have the ability to sense the direction and strength of Earth magnetic field, which they use for navigating along the turtles ‘regular migration route. Animals can also use mental maps like human beings. They just become familiar with an area and navigate using mountain ranges, coastlines, rivers and even, like dolphins, the shape of the sea floor. Smell is also a powerful tool for navigation. Salmon uses smell to find the exact stream that they were born.
Migratory birds are believed to use the stars, sun and other geographic features as guides. Night migrating birds are sometimes disoriented in prolonged heavy fog. Day- flying birds navigate by the sun and also make some use of geographic features , particularly of shorelines, most migratory birds travel within broad north-south air routes known as flyways. Some migratory bird’s winter only a few hundred miles from their breeding grounds, while other migrate between the cold or temperate zones of the two hemispheres. The longest journey is made by the Arctic tern, a small bird that flies from the Arctic to the Antarctic and back again each year.
Hazards of migration:
Not every animals or birds can return to own land. Many died, some lost the track, some never return by nature. For example, sea turtles never saw their children. The animals face two types of hazards during the time of migration - natural and human made. Natural hazards include climatic changes, drought, food scarcity, predators and the individual physical demands of migration on the animal. Sometimes the animal’s migratory behavior poses a considerable hazard as well. In southern Africa, for instance, springbok migrate in herds so dense that death from trampling, starvation, or drowning is not uncommon. Other animals caught in the springbok’s migration path suffer as well, often being swept along or trampled by the tide of rushing bodies.
Humans also posed particular dangers to migrating animals. For instance, the caribou of arctic regions are hunted by Inuit who intercept hers along seasonal migration routes. Sport hunters acquaint themselves with migration routes as well.
Human made structures like skyscrapers and radio towers have caused the deaths of hundreds of migrating birds. Water pollution has caused the fishes not to migrate to some specific areas.
Humans also posed particular dangers to migrating animals. For instance, the caribou of arctic regions are hunted by Inuit who intercept hers along seasonal migration routes. Sport hunters acquaint themselves with migration routes as well.
Human made structures like skyscrapers and radio towers have caused the deaths of hundreds of migrating birds. Water pollution has caused the fishes not to migrate to some specific areas.
your use of grammar is appalling. random commas and sentences that lead into others at irregular intervals.... topic is interesting though.
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